A Replacement for the 30%, 40%, and SRSS Rules for Multicomponent Seismic Analysis

Abstract

A response spectrum rule for combining the contributions from three orthogonal components of ground motion to the maximum value of a response quantity is presented. This rule, denoted CQC3, is compared to the 30% and 40% rules and the square-root-of-sum-of-squares (SRSS) rule currently specified in many design codes. It is shown that these current rules are special cases of the CQC3 rule, when certain conditions regarding the nature of the ground motion or the structural response are satisfied. Because these conditions are not always satisfied, it is argued that the CQC3 rule should be adopted as a general rule for the multicomponent combination problem. The CQC3 rule additionally offers a simple formula for determining the most critical orientation of the ground motion components for each response quantity of interest. The CQC3 rule is computationally simple and easy to implement in standard dynamic analysis codes.

Graphical Dynamic Trends for Earthquake Incidence Response of Plan-Asymmetric Systems

“…The comparison of the critical earthquake angle for the displacement response at different locations is reported in Table 1. Results indicate that the directions of the graphical modal trends given by the triangle of modal pivots/forces provide an accurate enough prediction of the critical angle as compared with the CQC3 rule [16], and with the RHA directional response envelope.…”

Wyznaczenie Modalnej Odpowiedzi Konstrukcji Na Wstrząsy Z Uwzględnieniem Kierunków Ich Działania

“…Bazując na tym założeniu Menun i Der Kiureghian [10] zaprezentowali kombinację CQC3, która uwzględnia zmienność działania trzęsienia w planie.…”

Structural Design Challenges in Design Certification Applications for New Reactors

“…In typical concrete design, however, multiple interacting response quantities are often considered. The combination methods for multiple interacting response quantities are distinctly different from those for a single response quantity [10][11][12][13][14][15][16].…”